END USER LEARNING BEHAVIOR IN DATA ANALYSIS AND DATA MODELING TOOLS

The research examined naive user analysts\u27 learning of data analysis skills; namely. (1) the difficulty of learning data analysis, (2) the differential learning rates among development tools, and (3) the dimensions of the tools contributing to the learning differences. A total of fifty-six students participated in two experiments. The experiments involved repeaied trials of practice and feedback in drawing application-based data models. On average, the participants were experienced end users of computer systems in organizations. The two tools examined in the experiments were the logical data structure model (LDS), which is based on the entity-relationship concept, and the relational data model (RDM). The correctness of the models improved over the trials in both LDS and RDM groups with LDS users performing better than RDM users, particularly in terms of representing relationships. LDS users were found to be more top-down motivated in their method of analysis than RDM users. The study suggests that among end users, the LDS formalism is more easily learned than the RDM formalism. The results also imply that end-user training should stress conceptual top*wn analysis, not bottom-up output directed analysis

Arp2/3 complex activity in filopodia of spreading cells

Background Cells use filopodia to explore their environment and to form new adhesion contacts for motility and spreading. The Arp2/3 complex has been implicated in lamellipodial actin assembly as a major nucleator of new actin filaments in branched networks. The interplay between filopodial and lamellipodial protrusions is an area of much interest as it is thought to be a key determinant of how cells make motility choices. Results We find that Arp2/3 complex localises to dynamic puncta in filopodia as well as lamellipodia of spreading cells. Arp2/3 complex spots do not appear to depend on local adhesion or on microtubules for their localisation but their inclusion in filopodia or lamellipodia depends on the activity of the small GTPase Rac1. Arp2/3 complex spots in filopodia are capable of incorporating monomeric actin, suggesting the presence of available filament barbed ends for polymerisation. Arp2/3 complex in filopodia co-localises with lamellipodial proteins such as capping protein and cortactin. The dynamics of Arp2/3 complex puncta suggests that they are moving bi-directionally along the length of filopodia and that they may be regions of lamellipodial activity within the filopodia. Conclusion We suggest that filopodia of spreading cells have regions of lamellipodial activity and that this activity affects the morphology and movement of filopodia. Our work has implications for how we understand the interplay between lamellipodia and filopodia and for how actin networks are generated spatially in cells

Degradation Kinetics and Mechanism of Antibiotic Ceftiofur in Recycled Water Derived from a Beef Farm

ISTC’s senior research scientist Wei Zheng collaborated with researchers from the Illinois State Water Survey, the U.S. Department of Agriculture, and the University of Illinois to determine the degradation kinetics of ceftiofur in liquid manure. Results were published in Xiaolin Li, Wei Zheng, Michael L. Machesky, Scott R. Yates, and Michael Katterhenry (2011). Journal of Agricultural and Food Chemistry 59(18), 10176-10181. DOI: 10.1021/jf202325c.Ope

Occurrence and Fate of the Herbicide Glyphosate in Tile Drainage and Receiving Rivers in East Central Illinois

Agricultural fields in the Midwestern United States are commonly tile-drained. This drainage system is used to remove excess water from the soil profile to increase crop production and promote soil conservation. However, subsurface tile drainage can readily deliver nutrients and pesticides from agricultural fields into surrounding watersheds. Glyphosate is a widely used pesticide in Midwestern agricultural fields, especially for modified glyphosate-resistant soybean and corn cultivars. The goal of this project was to develop a reliable and accurate analytical method to monitor the occurrence of glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), in tile drain water and receiving river water collected in east central Illinois agricultural lands. In this study, an isotopic dilution method was developed to analyze trace levels of glyphosate and AMPA in water using liquid chromatography-tandem mass spectrometry (LC-MS/MS), combined with pre-column derivatization and solid phase extraction for sample preparation. The method recoveries of glyphosate and AMPA during the whole monitoring period ranged from 85 to 120% and 83 to 147%, respectively. The limit of detection of the developed methods for glyphosate and AMPA was 0.10 μg/L with a relative standard deviation (RSD) of https://doi.org/10.1016/j.scitotenv.2018.09.387.Illinois Sustainable Technology Center Sponsored Research Program ; HWR17-245Ope

Occurrence and Fate of the Herbicide Glyphosate in Tile Drainage and Receiving Rivers in East Central Illinois

Agricultural fields in the Midwestern United States are commonly tile-drained. This drainage system is used to remove excess water from the soil profile to increase crop production and promote soil conservation. However, subsurface tile drainage can readily deliver nutrients and pesticides from agricultural fields into surrounding watersheds. Glyphosate is a widely used pesticide in Midwestern agricultural fields, especially for modified glyphosate-resistant soybean and corn cultivars. The goal of this project was to develop a reliable and accurate analytical method to monitor the occurrence of glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), in tile drain water and receiving river water collected in east central Illinois agricultural lands. In this study, an isotopic dilution method was developed to analyze trace levels of glyphosate and AMPA in water using liquid chromatography-tandem mass spectrometry (LC-MS/MS), combined with pre-column derivatization and solid phase extraction for sample preparation. The method recoveries of glyphosate and AMPA during the whole monitoring period ranged from 85 to 120% and 83 to 147%, respectively. The limit of detection of the developed methods for glyphosate and AMPA was 0.10 μg/L with a relative standard deviation (RSD) of https://doi.org/10.1016/j.scitotenv.2018.09.387.Illinois Sustainable Technology Center Sponsored Research Program ; HWR17-245Ope

Cell–substrate adhesion drives Scar/WAVE activation and phosphorylation by a Ste20-family kinase, which controls pseudopod lifetime

The Scar/WAVE complex is the principal catalyst of pseudopod and lamellipod formation. Here we show that Scar/WAVE’s proline-rich domain is polyphosphorylated after the complex is activated. Blocking Scar/WAVE activation stops phosphorylation in both Dictyostelium and mammalian cells, implying that phosphorylation modulates pseudopods after they have been formed, rather than controlling whether they are initiated. Unexpectedly, phosphorylation is not promoted by chemotactic signaling but is greatly stimulated by cell:substrate adhesion and diminished when cells deadhere. Phosphorylation-deficient or phosphomimetic Scar/WAVE mutants are both normally functional and rescue the phenotype of knockout cells, demonstrating that phosphorylation is dispensable for activation and actin regulation. However, pseudopods and patches of phosphorylation-deficient Scar/WAVE last substantially longer in mutants, altering the dynamics and size of pseudopods and lamellipods and thus changing migration speed. Scar/WAVE phosphorylation does not require ERK2 in Dictyostelium or mammalian cells. However, the MAPKKK homologue SepA contributes substantially—sepA mutants have less steady-state phosphorylation, which does not increase in response to adhesion. The mutants also behave similarly to cells expressing phosphorylation-deficient Scar, with longer-lived pseudopods and patches of Scar recruitment. We conclude that pseudopod engagement with substratum is more important than extracellular signals at regulating Scar/WAVE’s activity and that phosphorylation acts as a pseudopod timer by promoting Scar/WAVE turnover

FSCN1 and epithelial mesenchymal transformation transcription factor expression in human pancreatic intraepithelial neoplasia and ductal adenocarcinoma

Background: The actin regulatory protein fascin (FSCN1) and epithelial mesenchymal transition (EMT) transcription factor (TF) SLUG/SNAI2 have been shown to be expressed in PDAC and its precursor lesions (pancreatic intraepithelial neoplasia (PanIN), graded 1-3) in in vitro and murine in vivo studies. Our aim was to investigate the expression of FSCN1 and EMT-TFs and their association with survival in human PanIN and PDAC. Methods: Expression was investigated in silico using TCGA PanCancer Atlas data (177 PDAC samples with mRNA data) and immunohistochemical staining of a tissue microarray (TMA) (59 PDAC patients). Results: High FSCN1 expression was associated with poorer overall survival (p = 0.02) in the TCGA data. EMT-TF expression was not associated with survival, however FSCN1 expression correlated with that of the EMT-TFs SLUG/SNAI2 (rho = 0.49, p<0.001) and TWIST1 (rho = 0.52, p<0.001). TMA IHC showed low expression of SNAI2 and TWIST1 in normal ductal epithelium, while FSCN1 was not expressed. SNAI2 increased slightly in PanIN1-2, then decreased in higher grade lesions. TWIST1 increased in PanIN2-3 and was retained in PDAC. FSCN1 was increasingly expressed from PanIN2 onwards. SNAI2 and TWIST1 expression positively correlated in all grades of PanIN and PDAC (rho = 0.52, p<0.001). FSCN1 correlated positively with SNAI2 in PanIN1 (rho = 0.56, p<0.01). Conclusions: Increased expression of EMT-TFs in low-grade PanIN followed by FSCN1 in PanIN3 and PDAC suggests EMT-TFs may trigger FSCN1 expression and are potential early diagnostic markers. FSCN1 expression correlated with overall survival in PDAC and may have value as a prognostic marker

Mitochondrial permeabilization engages NF-κB-dependent anti-tumour activity under caspase deficiency

Apoptosis represents a key anti-cancer therapeutic effector mechanism. During apoptosis, mitochondrial outer membrane permeabilization (MOMP) typically kills cells even in the absence of caspase activity. Caspase activity can also have a variety of unwanted consequences that include DNA damage. We therefore investigated whether MOMP-induced caspase-independent cell death (CICD) might be a better way to kill cancer cells. We find that cells undergoing CICD display potent pro-inflammatory effects relative to apoptosis. Underlying this, MOMP was found to stimulate NF-κB activity through the downregulation of inhibitor of apoptosis proteins. Strikingly, engagement of CICD displays potent anti-tumorigenic effects, often promoting complete tumour regression in a manner dependent on intact immunity. Our data demonstrate that by activating NF-κB, MOMP can exert additional signalling functions besides triggering cell death. Moreover, they support a rationale for engaging caspase-independent cell death in cell-killing anti-cancer therapies